Aspects describe air flow relief features in the cosmetic surface of the housing of an in-ear audio output device. Due to design constraints based, at least in part, on the limited space available in the acoustic chamber and ear geometry, ports coupling the acoustic chamber with an area outside the housing are susceptible to full blockage when placed in-ear. Air flow relief channels for ports, extending from the port aligned in the concha cymba, over the helix crus, to the cymba cavum minimize complete blockages of the port as compared to current designs.